The City Dark, a new documentary by Ian Cheney has the deceptively modest goal of exploring just one tiny aspect of “human progress”—the use of artificial light to conquer the night. Ostensibly The City Dark is about light pollution, that is, light spilling into places we don’t want or intend it to go: the night sky, natural animal habitat, our very bedrooms What the film actually achieves is much greater than its initial grasp, as The City Dark paints a provocative portrait of a species caught up in a difficult coming of age, at once realizing our tiny place in a huge universe while growing ever more self-absorbed and intoxicated with our own power to re-engineer our reality.
The City Dark begins with Cheney contrasting his childhood in rural Maine with his life now in New York City. He tries to take stock of all he’s gained, and all he’s left behind, including a night sky filled with stars. He performs a little experiment that any urbanite will find obvious but may stun rural folk used to a rich night sky; he ventures out into Time Square…to stargaze.
Of course he fails to find more than a few stars of the 7,000 or so that are visible to the naked human eye in an unpolluted night sky. The sky in Times Square is not obscured by clouds, but by the very glow of the city itself. Two-thirds of humanity now live under light polluted skies, Cheney tells us. “I had never stopped to wonder what those dark, starry nights meant to me, but when I moved to the city, I felt at once like I was at the center of the world under all those lights, and like I’d left something important behind. What do we lose, when we lose the night?”
Quite a lot, as the rest of The City Dark points out with the same gentle reflectiveness; it is one of the filmmaker’s strengths that he speaks very little in the film overall, and when he does speak it’s not blunt rhetoric but rather enveloping poetry (set to a haunting score by the Fisherman Three and Ben Fries). The City Dark would be a very different film helmed by the likes of a Michael Moore. Cheney realizes the damage a bull could in this china shop, so he tiptoes through modernity, slowly building up to the inescapable conclusion that not only is light pollution a big problem, but that it’s one central to our troubled ecological moment.
The City Dark’s first two acts rely on astronomers (both amateur and professional) to tell the story of our loss of the night sky, backed up by attractive animation and compelling astrophotography. Stargazers will find this section particularly satisfying. We ride shotgun with Sam Storch, a New York City amateur, on the ride out to Jones Beach, where he used to observe. “As I’ve gotten older,” Storch laments from the driver’s seat, “I notice I have to go farther and farther from where there’s civilization in order to see the sky, to be part of the universe.” Later, as he surveys what looks like a post-apocalyptic beach scene with a sky the orange color of sodium lamps, Storch says: “It’s so sad, because I know what’s above me when it gets dark, it just doesn’t get dark any more.” As an amateur astronomer with a similar appreciation for the grandeur of the universe, I couldn’t have said it better myself.
This consistent eloquence is one of the most satisfying qualities of The City Dark, even when its subjects cannot speak. Sea turtles, for example. Cheney documents their harrowing birth on the Florida coast and bears witness to the deadly trick electric lights play on them. Well served again by the twinkling animation created for the film by Sharon Shattuck, The City Dark explains that sea turtles have evolved to recognize that the direction to the ocean is marked by the brightest horizon; the ocean surface simply reflects more starlight and moonlight than the land. With development all along the coast, however, the hapless sea turtle hatchlings, who have only a few minutes to get to the relative safety of the water, tend to go the wrong way, with predictably sad results. “Every summer,” Cheney says, “tens of thousands of turtles, already an endangered species, are lost to disorientation.”
A good storyteller would know upon speaking the last word of that sentence that they’ve uncovered the central metaphor of their tale, and would set the rest of the film to revolve around that point. Cheney is a good storyteller, and eventually he comes back to the ramifications of disorientation on humans. But here his interest is epidemiological; human life (among others) evolved over billions of years with clearly delineated days and nights. What does it do to our bodies when we live in a “city that never sleeps”? As with the rest of the strange story of light pollution, the answer is much more than you’d expect.
The City Dark delves into emerging science that links the high incidence of breast cancer in shift workers across the world to exposure to artificial light at night, which seems to impact the production cycle of the hormone melatonin. This chapter of the film has been unfairly dismissed by some reviewers as “suspect,” though they offer no counter evidence or argument why it should be discounted out of hand. Perhaps the problem here is Cheney’s evenhandedness. Viewers are used science being presented in emphatic, bombastic headline form, not as a nuanced conversation about slowly emerging knowledge. The City Dark actually does a great service to science by presenting the process authentically. Cheney presents the health risks of exposure to light at night (when the human body expects it to be dark) as not yet a fully supported theory, but a hypothesis with growing support in experimental and clinical studies. While humans are mightily adaptable, there are likely, it turns out, some steep hidden costs to our desire to burn the candle at both ends.
The City Dark gives a fair shake to the good intentions that drive increased outdoor lighting, encapsulated by the story of a burglary in his grandparent’s rural Maine home that motivates them to put up a big sodium lamp, as well as a case study of a urban park transformed by light into a safer community space. Surely there are good reasons to light and good ways of doing it; the trick is as always balance. As a bit of an anarchist, I liked the subtle evocation of another governmental motivation for lighting the darkness: to keep better tabs on the activities of its citizens, be they criminal or political. Remember that not just crime, but also revolutions and social movements (like our own Revolution against British Rule) were plotted and executed under the secrecy afforded by a little darkness.
The City Dark’s final act is, perhaps fittingly, the story of a quiet revolution, as a small town in Maine votes for an ordinance to control light pollution and preserve its dark skies. For its complex of deleterious effects, light pollution is actually not a difficult problem to fix, at least, in smaller towns and cities. Light pollution is largely a matter of waste—light going where we really don’t want or need it to go. There are enticing economic motivations for fixing it, if the spiritual, environmental and public health concerns aren’t compelling enough.
The voices of the film’s well-selected experts return to us at the end of The City Dark, bringing back with them this idea of humanity in the midst of a tumultuous coming of age. “And what is coming of age,” asks Ann Druyan, author and Carl Sagan’s widow, “but realizing that you are not the center of the universe?” Just when we need that perspective the most, we seem intent on blotting it out of common view. It’s possible that when the lights come up after Ian Cheney’s elegy to night-that-was, they will be seen as rude interlopers by an audience who, perhaps for the first time, will actually crave a little darkness.
Learn more about the film at The City Dark website. And watch the trailer, below: